Moving apparatus for a toy vehicle

ABSTRACT

APPARATUS FOR BRIEFLY PROPELLING AN UNPOWERED TOY VEHICLE SO IT THEN COAST AROUND A TRACK, COMPRISING A RAPIDLY ROTATING SCREW FOR ENGAGING A PROJECTION ON THE VEHICLE TO MOVE IT ALONG THE TRACK. THE SCREW HAS A VARI-   ABLE PITCH THT IS GREATEST AT DOWNPATH PORTIONS, SO THE VEHICLE IS ACCELERATED EVEN THOUGH THE SCREW MAY TURN AT A CONSTANT SPEED.

Sept. 20, 1971 1', 5. SEE ETAL 3,605,631

MOVING APPARATUS FOR A TOY VEHICLE Filed Dec; 5, 1968 z Sheets-Sheet 1 Awzwra: 74/0!!! fl! Arm me z'mwwuo 141v: 51w) Sept. 20, 1971 5,555 EFAL MOVING APPARATUS FOR A TOY VEHICLE 2 Sheets-Sheet 2 Filed Dec. 5, 1968 United States Patent Office U.S. Cl. 104-167 Claims ABSTRACT OF THE DISCLOSURE 1 Apparatus for briefly propelling an unpowered toy vehicle so it can then coast around a track, comprising a rapidly rotating screw for engaging a projection on the vehicle to move it along the track. The screw has a variable pitch that is greatest at downpath portions, so the vehicle is accelerated even though the screw may turn at a constant speed.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to toy vehicles and to apparatus for moving toy vehicles.

Description of the prior art Unpowered toy vehicles may be moved along a path by initially pushing them by hand or allowing them to initially move doWn an incline. These methods require a child to repeatedly handle the vehicle after each run along its path, to push it or to again place it at the top of an incline. Repeated handling can be annoying and it tends to destroy the entertaining illusion of vehicles moving by themselves.

OBJECTS AND SUMMARY OF THE INVENTION An object of the present invention is to provide simple and economical apparatus for accelerating toy vehicles.

Another object of the invention is to provide apparatus for accelerating toy vehicles in a smooth and controlled manner.

In accordance with the present invention, a screw-like member is provided for engaging a toy vehicle to accelerate it along a path. The screw-like member may be provided with a variable pitch, the pitch generally increasing with downpath portions. Accordingly, even if the screw is rotated at a constant speed, it accelerates the vehicles.

In one embodiment of the invention, the screw-like member comprises a wire wound in a helix of variable pitch. The helix is held in a long tube that supports it as it rotates. The tube is positioned along the middle of the track so that vehicles pass over it, and a slot is provided along the length of the tube to enable a downwardly projecting element on the vehicles to engage the helix. The Walls of the slot also aid in guiding vehicles so they are not moved sideways by frictional contact with the rotating helix. In another embodiment of the invention, a rod is provided with a thread of variable pitch formed in it. In either of the embodiments, the screw can be turned by an electric motor or by other means.

The novel features of the invention are set forth with particularity in the appended claims. The invention will be best understood from the following description when read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a portion of a track layout with a toy vehicle accelerator constructed in accordance with the invention;

' FIG. 2 is a plan view of the toy vehicle accelerator, taken on the line 22-of FIG. 1;

Patented Sept. 20, 1971 DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates a portion of a track layout for guiding unpowered toy vehicles. The layout is generally formed by several track sections connected in series, and may include loops, curves, and other interesting portions. In accordance with the invention, a frame 12 is provided which carries a short track section 14 that is normally connected in series with a straight-away portion of the track layout. The frame carries apparatus for accelerating a toy vehicle so that it can coast a considerable distance along the rest of the track. In small track layouts, one accelerating apparatus may be suflicient to send the vehicle completely around the track, while larger layouts may require more than one accelerating mechanism. Thus, if the accelerating mechanism is powered by electricity or the like, it can provide vehicle motion indefinitely.

As shown in FIGS. 2 and 3, the track section 14 defines a track surface 16 with opposite sides along which the wheels of a vehicle can roll, and guide rails 18 and 20 for assuring confinement of the vehicle to movement along the track. An elongated slot 22 is formed along the center of the track surface, and a screw 24 is positioned below the slot. A vehicle 26 is provided with a projecting member 28 that depends downwardly therefrom. The member 28 can project through the slot to engage the screw. The screw is rotatably mounted and is driven by an electric motor 30. When the coasting vehicle 26 reaches the track section 16 and its projection 28 engages the rotating screw, the screw accelerates the vehicle as it moves it downpath, so the vehicle can thereafter coast along the track layout.

The screw 24 is constructed of a long length of Wire wound in a helix of variable pitch. The pitch of the helix is smallest near its up-path end 32 and continually increases until it reaches a maximum level at its downpath end 34. The extreme up-path end is wound in a tight spiral at 36 for rigidity, and an arbor 38 is inserted into the portion 36 to support it. The arbor has a trunnion 40' that engages a bearing hole 42 in the frame to enable its free rotation. The downpath portions of the helix are supported by a tube 44 that surrounds the helix. The tube has a slot in it which forms a part of the slot 22 in the track. Thus, the screw 24 is constructed for economical manufacture, yet it can be readily mounted for rapid rotation.

Most of the track layout does not have a central slot in it, and therefore the projection 28 on the toy vehicle lies above the level of the track surface 16. The portion of the screw 24 which is designed to engage the vehicle projection lies at a level slightly above the track surface 16, as can be best seen in FIG. 5. A pair of walls 46 and 48 are provided on either side of the slot 22. to help guide the vehicle, the tube slot Walls forming part of the walls 46 and 48. When the screw pushes the vehicle along, friction between the protuberance 28 and the wire of the screw tends to divert the vehicle to one side. The walls 46 and 48 prevent excessive sideward drifting of the vehicle. The extreme up-path ends 50 and 52 of the slot walls converge slightly in a downpath direction, to aid in guiding the vehicle projection 28 along the slot.

The tightly wound up-path portion 36 of the screw is too tightly Wound to accept the projection 28 between adjacent helical turns. In order to prevent the projection 28 from abutting this portion and being stopped by it, the portion 36 is wound with a smaller diameter than the rest of the screw, so that it lies below the level of the projection 28. Immediately downpath from the tightly wound portion 36, where the space between adjacent helical turns is sufiicient to receive the projection 28, the diameter of the helix is great enough to engage the projection.

The motor 30 which rotates the screw is powered by a pair of batteries 54 and 56 which are held in a case portion of the frame. The motor has a pulley 58 that is coupled by a belt 60 to the arbor 3-8. The arbor 38, which is fixed to the screw 24, has a pulley groove 62 around which the belt extends. The diameter of the arbor, even with the belt thereon, is sufficiently small to prevent interference with the vehicle projection. The motor 30 generally turns at a sufliciently high speed to rapidly rotate the screw 24. This allows a screw to propel the vehicle so that it attains a high final velocity, such as 12 feet per second. The wire from which the helix is constructed is generally flexible, so that it can be compressed like a spring by the vehicle projection. The energy thus stored during the first several turns, while propelling a vehicle, can be released during the last few turns to help maintain a high vehicle acceleration throughout its contact with the screw, to help yield a high final speed.

Generally, a child closes a motor switch 64 to enable continuous rotation of the screw 24 during play. He then places a toy vehicle on the track layout immediately uppath from the accelerator mechanism and pushes the vehicle so it enters the mechanism. The screw 24 then accelerates the vehicle sufiiciently so that it coasts around the track (sometimes with the aid of additional screw type accelerating mechanisms spaced around the track) until it again enters the accelerating mechanism for another propulsion.

FIG. 6 illustrates another embodiment of the invention, wherein a screw 70 is formed by a rod with a helical groove or thread 72 formed therein. A variety of thread forms may be used, an acme or square thread generally being most suitable. The rod 70 is supported by a pair of trunnions 74 and 76 at either end that engage bearing holes 78 and 80 on the frame 81. A rod portion 82 of reduced diameter has a pulley groove 84 therein. A belt 86 driven by a motor 88 rapidly rotates the rod. While the solid screw of FIG. 6 is generally somewhat more expensive to manufacture, the ability to rotatably support it by trunnions at either end, often allows for smaller friction to enable rapid rotation by a small horsepower motor. The greater mass of a solid screw allows it to store energy so it is not appreciably slowed by accelerating a vehicle. In addition, the groove or thread 72 can be made and maintained with a more regular pitch function for smoother vehicle acceleration and less side thrust. The side thrust can sometimes be reduced to the extent where slot walls are not necessary to prevent excessive sideward movement of the vehicle.

A variety of pitch functions can be utilized for the screws. One function which is desirable provides a uniform acceleration throughout almost the entire length of the thread that engages the vehicle. This produces an almost constant load on the motor. While an electric motor is shown, a variety of other types can be employed, such as a spring wound motor. In addition, a hand-operated motor can be used, such as a wheel with a knob for hand turning and a speed increasing gear train for connecting the wheel to the screw. While a hand-operated mechanism requires attendance by a child, it enables him to accelerate a vehicle without actually handling it. The level of acceleration which he can thus achieve is generally greater than he can readily achieve by propelling the vehicle by hand, and it allows for greater accuracy to maintain the vehicle on the track.

While a screw with variable pitch and substantially constant rotation can be used, it is also possible to employ a screw with almost constant pitch and motor means that rapidly increases its speed of rotation. Thus, for example, a spring powered motor can be employed which is started only when a vehicle begins to engage the screw. Such a motor can then rapidly accelerate the screw to a high speed of rotation, to thereby accelerate the vehicle using a screw of constant pitch. Generally, however, a screw with a pitch that increases in the downpath direction is desirable. The screw can also be used to move a vehicle up an incline so that it can thereafter coast downhill. In such a case it is not necessary that the vehicle be accelerated, although the vehicle can be accelerated as well as lifted.

The vehicle projection 28 can be constructed in a number of ways. While a rigid projection which extends to a position above the Wheels of the vehicle has been described, a flexible or pivotally mounted projection can be used which normally bears against the bottom of the roadway, but which engages a screw at the accelerating mechanism. However, such a projection generally would increase the friction of the vehicle on the track surface and limit the distance over which it can coast.

Although particular embodiments of the invention have been described and illustrated herein, it is recognized that modifications and variations may readily occur to those skilled in the art, and consequently it is intended that the claims be interpreted to cover such modifications and equivalents.

What is claimed is:

1. In a track system for a vehicle toy rolling on a track surface comprising:

a miniature freely rolling toy vehicle having a downwardly extending screw engaging member, the lowest extremity of which member lies above said track surface;

a track section disposed in series with said track system, said section including said track surface, the wheels of said vehicle rolling on opposite sides of said track surface, said section also including an elongated slot along the center of said track surface between said opposite sides;

a screw member rotatably mounted generally parallel to and below said elongated slot in said track section with an upper portion of said screw member extending through said elongated slot only a sufficient amount to contact said screw engaging member, said screw member including thread means with an up-path end for initially engaging said toy vehicle coasting at a relatively slow speed and with a down-path end whereat said vehicle disengaged at a relatively high speed to coast along said track system, said thread means continually increasing in pitch with downward path position at least along a portion of its length; and

motor means operatively coupled to said screw member for rotating said screw member at a desired rotational speed.

2. The apparatus of claim 1, wherein said track section also includes slot defining side walls along the length of said elongated slot to limit any sideward shifting of said vehicle, said side walls extending above said track surface but not an amount to contact said toy vehicle.

3. The apparatus of claim 2, wherein the extreme uppath ends of said slot defining Walls converge slightly in a down-path direction to aid in guiding said toy vehicle.

4. An accelerator accessory for use with a miniature freely rolling toy vehicle of the type having wheels for rolling on a track surface of a track system and having a depending projection not extending below the vehicle as far as the track surface, the depending projection following a predetermined path, the accessory comprising:

an elongated track section having a rolling surface coplanar and in series with said track surface and having slot walls defining an elongated slot in said rolling surface, the slot being in alignment with said predetermined path; an elongated screw member rotatably mounted below said track section with its longitudinal axis parallel to the longitudinal dimension of said track section and its upper perimeter portion extending through said slot only an amount to cooperate with a depending projection, said screw member including thread means with an up-path end for initially slidably engaging said depending projection entering at the relatively slow speed and with a down-path end whereat said depending projection is disengaged at a relatively high speed; and

motor means operatively coupled to said screw member for rotating said screw member at a rotational speed whereby said toy vehicle is accelerated.

5. The accessory according to claim 4, wherein said thread means is continually increasing in pitch with down-path position.

6. The accessory according to claim 4, wherein the extreme up-path end of said slot walls converge slightly in a down-path direction.

7. The accessory according to claim 4, wherein said track section includes side guide walls projecting above said rolling surface on opposite sides thereof.

, 8. The accessory according to claim 4, wherein said screw member is a rod and said thread means is a helical groove formed in said rod.

9. The accessory according to claim 4, wherein said screw member is a wire wound in a helical configuration and said thread means is the spacing between the turns of said helical configuration.

10. The accessory according to claim 9, including a tube disposed about said screw member with an upwardly disposed slot extending along its length in alignment with said predetermined path.

References Cited ARTHUR L. LA POINT, Primary Examiner R. SAIFER, Assistant Examiner U.S. Cl. X.R. 46-206 

